1. Field of the Invention
The present invention relates to a latch assembly for holding an object in either of two positions. More particularly, this invention relates to such a latch assembly that advantageously may be used to hold, for example, a pivotable door in either its closed position or its open position displaced 180 or 270 degrees from its closed position.
There are many structures in which a simple yet reliable latching mechanism is desirable for holding a closure like a door in either an open or a closed position. For example, delivery/storage cabinets used to transport and store food trays in bakeries or food service institutions typically have a door mounted for pivoted movement between a closed position retaining the trays in the cabinet interior, and an open position providing access to the interior. (A food service institution is generally understood to be one, such as a restaurant, cafeteria, school lunch facility or the like, in which food is prepared to be taken out or consumed on the premises.) When swung to the closed position, the door should automatically and positively latch in order to prevent the trays from falling out of the cabinet. Similarly, when swung to the open position, the door should also automatically and positively latch so as not to interfere with removal of trays from or return to the cabinet interior and so as not to obstruct the area in which the cabinet may temporarily be located. Furthermore, for convenience of the user, the latch assembly should be manipulable with one hand to release the door from either the latched open or the latched closed position.
Of course, there are many other applications for a simple latch assembly that holds an object in either of two positions and that may be conveniently manipulated to release the object from those positions.
2. Description of the Prior Art
Many types of latches for securing a door in an open or a closed position are presently known. Some operate under the influence of gravity to move to a latched condition while others incorporate a mechanism such as a spring for this purpose.
For example, storage and transport cabinets sold under the name CRES-COR by Crescent Metal Products, Inc., 12711 Taft, Cleveland, Oh. 44108, and denoted 100 Series, 100-SD Series, 150 Series, 101 Series, 101-MP, 100-MP, 101-MM Series, and 115-AP Series, incorporate a latch mounted on the cabinet, not on the cabinet door, that tends to move to the latched condition under the influence of gravity. However, in operation the latch is first moved manually to an unlatched position prior to latching operation.
Mobile cabinets available from Normandie, 133-14 Jamaica Avenue, Richmond Hill, N.Y., 11418, incorporate a latch similar to that used on the Crescent Metal Products cabinets.
Cabinets sold under the name TRANSITRAY CABINET, by Bevles Company, Inc., 2121 Central Avenue, South El Monte, Calif. 91733, incorporate a gravity operated latch. However, it is believed that this latch must be manipulated to secure the door in either the open or closed position.
Thus, latches known in the art such as those briefly discussed above are characterized by certain drawbacks.